Immunity in humans; protecting against overreaction (Introduction)

by David Turell , Tuesday, November 01, 2016, 14:45 (2725 days ago) @ David Turell

When B cells are turned on to produce new antibodies, there is a control mechanism from neutrophils to control the reaction from overreaction:

https://www.sciencedaily.com/releases/2016/11/161101093250.htm

"It has long been known that a certain type of cell in the inherited immune system called a neutrophil plays an important part in wound healing and the early stages of the immune response. Through their studies on laboratory mice, the team from KI has now discovered that neutrophils have another crucial function in their interaction with B lymphocytes. What they found was a safety mechanism that prevents B lymphocytes from reacting to endogenous antigens.

"When an inflammation occurs in the body, the neutrophils cause the B lymphocytes in the spleen to start producing antibodies that retard an infection. At the same time, however, the neutrophils also communicate with a kind of immune cell called an NKT cell, instructing it to regulate the response to prevent over-reaction.

"It is known that SLE patients do not have as many NKT cells as other people, which could be a contributing factor to the failure of the body to regulate B lymphocytes.

"'Apart from our discovery being interesting in general terms of how the immune system works, it can also be very important for people with other autoimmune diseases," says Professor Karlsson. "We think that this mechanism could be used to regulate B lymphocytes in different morbid conditions and that it could be a way forward for stopping SLE.'"

Comment: SLE, systemic lupus erythematosus affects many parts of the body and can be fatal. More in woman by a rate of about seven to one. This is an excellent example of the automatic feedback loops that have to be present in complex biologic systems to maintain molecular reactions within proper controlled limits. If it isn't present from the beginning, controls would have to be developed in a step-wise fashion. Not likely as there would be damage or death before the controls developed. Saltation is the only way.